release/src/router/busybox/editors/sed_summary.htm

   1 <html>
   2
   3 <head><title>Command Summary for sed (sed & awk, Second Edition)</title>
   4 </head>
   5
   6 <body>
   7
   8 <h2>Command Summary for sed</h2>
   9
  10 <dl>
  11
  12 <dt><b>: </b> <b> :</b><em>label</em></dt>
  13 <dd>Label a line in the script for the transfer of control by
  14 <b>b</b> or <b>t</b>.
  15 <em>label</em> may contain up to seven characters.
  16 (The POSIX standard says that an implementation can allow longer
  17 labels if it wishes to. GNU sed allows labels to be of any length.)
  18 </p></dd>
  19
  20
  21 <dt><b>=</b> [<em>address</em>]<b>=</b></dt>
  22 <dd>Write to standard output the line number of addressed line.</p></dd>
  23
  24
  25 <dt><b>a</b> [<em>address</em>]<b>a\</b></dt>
  26 <dd><em>text</em></p>
  27
  28 <p>Append <em>text</em>
  29 following each line matched by <em>address</em>.  If
  30 <em>text</em> goes over more than one line, newlines
  31 must be "hidden" by preceding them with a backslash.  The
  32 <em>text</em> will be terminated by the first
  33 newline that is not hidden in this way.  The
  34 <em>text</em> is not available in the pattern space
  35 and subsequent commands cannot be applied to it.  The results of this
  36 command are sent to standard output when the list of editing commands
  37 is finished, regardless of what happens to the current line in the
  38 pattern space.</p></dd>
  39
  40
  41 <dt><b>b</b> [<em>address1</em>[,<em>address2</em>]]<b>b</b>[<em>label</em>]</dt>
  42 <dd>Transfer control unconditionally (branch) to
  43 <b>:</b><em>label</em> elsewhere in
  44 script.  That is, the command following the
  45 <em>label</em> is the next command applied to the
  46 current line.  If no <em>label</em> is specified,
  47 control falls through to the end of the script, so no more commands
  48 are applied to the current line.</p></dd>
  49
  50
  51 <dt><b>c</b> [<em>address1</em>[,<em>address2</em>]]<b>c\</b></dt>
  52 <dd><em>text</em></p>
  53
  54 <p>Replace (change) the lines selected by the address with
  55 <em>text</em>.  When a range of lines is specified,
  56 all lines as a group are replaced by a single copy of
  57 <em>text</em>.  The newline following each line of
  58 <em>text</em> must be escaped by a backslash, except
  59 the last line.  The contents of the pattern space are, in effect,
  60 deleted and no subsequent editing commands can be applied to it (or to
  61 <em>text</em>).</p></dd>
  62
  63
  64 <dt><b>d</b> [<em>address1</em>[,<em>address2</em>]]<b>d</b></dt>
  65 <dd>Delete line(s) from pattern space.  Thus, the line is not passed to standard
  66 output. A new line of input is read and editing resumes with first
  67 command in script.</p></dd>
  68
  69
  70 <dt><b>D</b> [<em>address1</em>[,<em>address2</em>]]<b>D</b></dt>
  71 <dd>Delete first part (up to embedded newline) of multiline pattern space created
  72 by <b>N</b> command and resume editing with first command in
  73 script.  If this command empties the pattern space, then a new line
  74 of input is read, as if the <b>d</b> command had been executed.</p></dd>
  75
  76
  77 <dt><b>g</b> [<em>address1</em>[,<em>address2</em>]]<b>g</b></dt>
  78 <dd>Copy (get) contents of hold space (see <b>h</b> or
  79 <b>H</b> command) into the pattern space, wiping out
  80 previous contents.</p></dd>
  81
  82
  83 <dt><b>G</b> [<em>address1</em>[,<em>address2</em>]]<b>G</b></dt>
  84 <dd>Append newline followed by contents of hold space (see
  85 <b>h</b> or <b>H</b> command) to contents of
  86 the pattern space.  If hold space is empty, a newline is still
  87 appended to the pattern space.</p></dd>
  88
  89
  90 <dt><b>h</b> [<em>address1</em>[,<em>address2</em>]]<b>h</b></dt>
  91 <dd>Copy pattern space into hold space, a special temporary buffer.
  92 Previous contents of hold space are wiped out.</p></dd>
  93
  94
  95 <dt><b>H</b> [<em>address1</em>[,<em>address2</em>]]<b>H</b></dt>
  96 <dd>Append newline and contents of pattern space to contents of the hold
  97 space.  Even if hold space is empty, this command still appends the
  98 newline first.</p></dd>
  99
 100
 101 <dt><b>i</b> [<em>address1</em>]<b>i\</b></dt>
 102 <dd><em>text</em></p>
 103
 104 <p>Insert <em>text</em> before each line matched by
 105 <em>address</em>. (See <b>a</b> for
 106 details on <em>text</em>.)</p></dd>
 107
 108
 109 <dt><b>l</b> [<em>address1</em>[,<em>address2</em>]]<b>l</b></dt>
 110 <dd>List the contents of the pattern space, showing nonprinting characters
 111 as ASCII codes.  Long lines are wrapped.</p></dd>
 112
 113
 114 <dt><b>n</b> [<em>address1</em>[,<em>address2</em>]]<b>n</b></dt>
 115 <dd>Read next line of input into pattern space.  Current line is sent to
 116 standard output.  New line becomes current line and increments line
 117 counter.  Control passes to command following <b>n</b>
 118 instead of resuming at the top of the script.</p></dd>
 119
 120
 121 <dt><b>N</b> [<em>address1</em>[,<em>address2</em>]]<b>N</b></dt>
 122 <dd>Append next input line to contents of pattern space; the new line is
 123 separated from the previous contents of the pattern space by a newline.
 124 (This command is designed to allow pattern matches across two
 125 lines.  Using \n to match the embedded newline, you can match
 126 patterns across multiple lines.)</p></dd>
 127
 128
 129 <dt><b>p</b> [<em>address1</em>[,<em>address2</em>]]<b>p</b></dt>
 130 <dd>Print the addressed line(s).  Note that this can result in duplicate
 131 output unless default output is suppressed by using "#n" or
 132 the <span class="option">-n</span>
 133
 134 command-line option.  Typically used before commands that change flow
 135 control (<b>d</b>, <b>n</b>,
 136 <b>b</b>) and might prevent the current line from being
 137 output.</p></dd>
 138
 139
 140 <dt><b>P</b> [<em>address1</em>[,<em>address2</em>]]<b>P</b></dt>
 141 <dd>Print first part (up to embedded newline) of multiline pattern space
 142 created by <b>N</b> command.  Same as <b>p</b>
 143 if <b>N</b> has not been applied to a line.</p></dd>
 144
 145
 146 <dt><b>q</b> [<em>address</em>]<b>q</b></dt>
 147 <dd>Quit when <em>address</em> is encountered.  The
 148 addressed line is first written to output (if default output is not
 149 suppressed), along with any text appended to it by previous
 150 <b>a</b> or <b>r</b> commands.</p></dd>
 151
 152
 153 <dt><b>r</b> [<em>address</em>]<b>r</b> <em>file</em></dt>
 154 <dd>Read contents of <em>file</em> and append after the
 155 contents of the pattern space.  Exactly one space must be put between
 156 <b>r</b> and the filename.</p></dd>
 157
 158
 159 <dt><b>s</b> [<em>address1</em>[,<em>address2</em>]]<b>s</b>/<em>pattern</em>/<em>replacement</em>/[<em>flags</em>]</dt>
 160 <dd>Substitute <em>replacement</em> for
 161 <em>pattern</em> on each addressed line.  If pattern
 162 addresses are used, the pattern <b>//</b> represents the
 163 last pattern address specified.  The following flags can be specified:</p>
 164
 165         <dl>
 166
 167         <dt><b>n</b></dt>
 168         <dd>Replace <em>n</em>th instance of
 169         /<em>pattern</em>/ on each addressed line.
 170         <em>n</em> is any number in the range 1 to 512, and
 171         the default is 1.</p></dd>
 172
 173         <dt><b>g</b></dt>
 174         <dd>Replace all instances of /<em>pattern</em>/ on each
 175         addressed line, not just the first instance.</p></dd>
 176
 177         <dt><b>I</b></dt>
 178         <dd>Matching is case-insensitive.<p></p></dd>
 179
 180         <dt><b>p</b></dt>
 181         <dd>Print the line if a successful substitution is done.  If several
 182         successful substitutions are done, multiple copies of the line will be
 183         printed.</p></dd>
 184
 185         <dt><b>w</b> <em>file</em></dt>
 186         <dd>Write the line to <em>file</em> if a replacement
 187         was done.  A maximum of 10 different <em>files</em> can be opened.</p></dd>
 188
 189         </dl>
 190
 191 </dd>
 192
 193
 194 <dt><b>t</b> [<em>address1</em>[,<em>address2</em>]]<b>t </b>[<em>label</em>]</dt>
 195 <dd>Test if successful substitutions have been made on addressed lines,
 196 and if so, branch to line marked by :<em>label</em>.
 197 (See <b>b</b> and <b>:</b>.)  If label is not
 198 specified, control falls through to bottom of script.</p></dd>
 199
 200
 201 <dt><b>w</b> [<em>address1</em>[,<em>address2</em>]]<b>w</b> <em>file</em></dt>
 202 <dd>Append contents of pattern space to <em>file</em>.
 203 This action occurs when the command is encountered rather than when
 204 the pattern space is output.  Exactly one space must separate the
 205 <b>w</b> and the filename.  A maximum of 10 different
 206 files can be opened in a script.  This command will create the file if
 207 it does not exist; if the file exists, its contents will be
 208 overwritten each time the script is executed.  Multiple write commands
 209 that direct output to the same file append to the end of the file.</p></dd>
 210
 211
 212 <dt><b>x</b> [<em>address1</em>[,<em>address2</em>]]<b>x</b></dt>
 213 <dd>Exchange contents of the pattern space with the contents of the hold
 214 space.</p></dd>
 215
 216
 217 <dt><b>y</b> [<em>address1</em>[,<em>address2</em>]]<b>y</b>/<em>abc</em>/<em>xyz</em>/</dt>
 218 <dd>Transform each character by position in string
 219 <em>abc</em> to its equivalent in string
 220 <em>xyz</em>.</p></dd>
 221
 222
 223 </dl>